Kamoa Copper has inked a deal with China Nerin Engineering Co for its direct-to-blister flash smelter.

The smelter will have a 500,000 tonnes per year capacity, and will be built next to the Phase 1 and Phase 2 concentrator plants. It will process the majority of the copper concentrate produced by Kamoa-Kakula's Phase 1, Phase 2, and Phase 3 concentrators, resulting in approximately 99% pure blister copper.

The smelter will also produce sulphuric acid as a by-product, creating an additional revenue stream for the mine.

China Nerin will build the smelter concurrently to the mine's Phase 3 mine and concentrator expansion, and the upgrading of turbine 5 at the Inga II hydropower complex.

The Phase 3 expansion and the on-site smelter will be powered by the additional 162 megawatts generated by the upgraded hydropower complex.

Basic engineering is expected to take seven months.

After basic engineering is completed, Kamoa Copper will order long-lead equipment. Earthworks on the project are slated to begin in the second quarter of 2022. Kamoa will award the Engineering, Procurement, and Construction Management contract after the earthworks are begun.

The total time to construct the smelter is expected to take three years, with a capital cost around US$700 million. This will be financed by cash flows from the mine.

China Nerin built the Lualaba copper smelter, which currently processes about a third of Kamoa's current concentrate output, Kamoa Copper chief executive Mark Farren said.

The smelter will incorporate technology from Metso Outotec, using a single flash furnace which eliminates the need for separate converting stages or ladle transportation. The process results in higher copper recovery, and has low capital and maintenance costs. The technology meets emissions standards set by the International Finance Corporation.

Building the smelter onsite will reduce the volume of copper concentrate shipped from the mine by approximately one half or more. It will also maximise in-country beneficiation, chief executive Farren said.

"Shipping 99%-pure blister copper ingots produced from an on-site smelter…will result in a significant reduction in Kamoa-Kakula's concentrate transportation costs and Scope 3 emissions," Farren said.

The Kamoa-Kakula copper project is a joint venture between Ivanhoe Mines (39.6%), Zijin Mining Group (39.6%), Crystal River Global (0.8%) and the government of the DRC (20%).